Missing him

How do I get over it? It has only been a few days since we have been broken up. The first few days I was fine, didn't miss or want him, and was actually relieved. But now... I don't know. I know I'm being dumb for even wanting him back in the first place, considering how horribly he treated me. The thing is, we still live together. Share meals, share a bed (though there's ample space kept between us, king-sized). Before you say "move out", I'm pregnant with his child, started maternity leave the week we broke up, and don't have my own money or anywhere else to go right now. Believe me, I've exhausted all my options. But I have stayed with my friend and am currently spending the weekend at my cousin's, and my friend told me I could stay with her again a few days this upcoming week. It just isn't comfortable. Maybe the reason I miss being with him is because it's what I'm used to? We were together (living included) for over two years. Why do I want to (and continue to) go back to someone who treated me so badly? I'm beginning to think something is inherently wrong with me... Please no negative or mean feedback, I'm an emotional and hormonal wreck as is.